Drive-chain



(No Model.) 2 Sheets-Sheet 1.

J. 0. BROWN.

DRIVE CHAIN v m m M 4 mm s, g m I. 1 i@ am (\I. W 0? I M 2 e H Tu". d /7 e t n 6 b 3 P b m mam k mm X N N my W J. 0. BROWN. DRIVE CHAIN.

2 Sheets-Sheet 2.

(No Model.)

No. 499,961. Patented June 20, 1893.

Illll UNITEIS STATES PATENT OFFICE.

JAMES 0. BROWN, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE NATIONAL CHAIN GEAR COMPANY, OF PORTLAND, MAINE.

DRIVE-CHAIN.

SPECIFICATION forming part of Letters Patent Nb. 499,961, dated. June 20, 1893.

Application filed December 5, 1892- serial No. 454,129. (No model.) I

To an whom it may concern:

Be it known that I, JAMES 0. BROWN, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Power-Transmitting Apparatus, of which the following is a specification.

This invention has for its object to enable a chain to communicate motion from one shaft to to another with greater economy of power and to better advantage than heretofore, and it consists, first, in a power-transmitting device, comprising a chain, composed of links, which are provided on their inner sides with gear I 5 teeth, and are arranged end to end in such manner that inward fiexure of the chain is prevented, and only such flexure is permitted as will permit the chain to pass freely around the gear wheels with which its teeth are engaged, so that the straight portions of the chain extending between the gear wheels constitute practically rigid racks, through one of which the driving-wheel imparts power to the driven wheel by pushing. 2 5' The invention also consists in'the combination with a chain such as that above indicated, of a support or supports arranged to prevent the outward ilexure of the chain between the pulleys, thus maintaining the chain in con- 0 'dition to transmit power by pushing.

The invention also consists in a chain composed of two or more rows of links, the links of each row breaking joints with those of the next, so that the teeth of'the chain exert a 5 continuous gripping action on the teeth of the gear wheel as hereinafter explained, for the purpose of preventing accidental separation:

of the chain from the gear wheel.

The invention also consists in certain other improvements, such as the provision of pock ets for lubricating material in the ends of the chain teeth, and the form and arrangement 'of the toothed links of the chain and of the connecting-plates which secure said links to: gether, all of which I will now proceed to describe and claim.

Of the accompanying.drawings, forming part of this specification: Figure 1 represents a side view of a gear wheel, and a portion of the chain that connects said wheel with another gear wheel, portions of the chain and a part of the wheel being shown in section. Fig.

2 represents a top view of a part of the chain. Fig. 2 represents a section on line 2-2, Fig. 1. Fig. 3 represents a perspective view of a portion of a chain. Fig. 4; represents a perspective view of one of the link-connecting plates. Fig. 5 represents a section on line 5-5, Fig. 2. Fig. 6 represents a perspective view of a portion of one of the gear wheels. Fig. 7 represents a side view of a gear wheel and a part of the chain, the latter being composed of a plurality of rows of links. Fig. 8 represents a section on line 8-S, Fig. 7. Fig.

9 represents a top view of the construction shown in Figs. 7 and 8, a portion of the chain being removed to expose the gear. Fig. 10 represents a perspective view of a portion of the chain shown in Figs. 7, 8 and 9.

The same letters of reference indicate the same parts in all the figures.

Referring first to Figs. 1 to 6 inclusive of the drawings, (t represents a gear wheel, affixed to a shaft a, and having suitably-formed gear teeth 0. The shaft a may be journaled in a suitable supporting-frame a and power may be applied to it in any suitable way.

1) represents the chain, which is composed of links I), eachhaving (preferably) two gear teeth b formed to engage the teeth a of the wheel. The links are connected in an endless row or seriesby plates or sub-links 19 each of which is pivoted at b b to the ends of the teeth of two links I), the pivots b being therefore located at one. side of the plane of the links. Thearrangement of the links is such that, when the chain is straight, the ends of each link abut against the ends of the adjacent links and against the plates 19 in such manner as to prevent flexure of the chain inwardly or toward the space surrounded by the chain, the pivots b being located inside the links or within said space, so that the end of each link constitutes a stop which prevents the endof the next link from swinging in- 5 wardly on its pivot. The straight portions of the chains are therefore practically rigid between the driving and the driven Wheels, so that one side of the chain acts as a rack, through which the driving-wheel exerts a IO'J pushing force on the driven wheel, the other portion of the chain receiving a pushing force frointhe'di-iven wheel.

The described form and arrangementof the links, their pivots and the connecting-plates, permit free outward flexure of the chain, so

I that it can readily conform to the peripheiy drivinganddrivenwheelsl' It will be seen,;-

passing 'over'the same, as"

straight portions of the" ehainisrendered in1-. possible ytes described c'on'struetion ofthe portions is rendered impossible by the "sto sf. or guides, thestr'aiglit portions of the *ciia n, constitute racks which areto allintentsand purposes rigid between the in'g anddrivn; wh s an ct ms ir s sfhdr s t flexibility, those portions of theicliai' when:

engage the gearwheels being jfree to awa conform to the p'eripheries'ot' saidwheels, as

above "described; prefer t out away te teeth b on" the chain li"nks, fo'"" receive the plates b ,so that the outer sildsofffs' aidiplates; will be practicallyflushwi the edges o'f'the ink jb'i h w" n i J and, r i 1 I p efr to 'provide'theteeth a otthe wheel" teeth, and to provide each offthe 'iilat'eszb with'aj recess b? 4), saidfre cesses"being? formed tobea'r upon the shoulders ai as! shown in 'F ig.'1j,"thus limiting'fthefdept of entrance of the teeth of "theichaiifinto tile spaces between thet'eeth or tiiegeanahiijpre venting the chain teeth fron'isti'dling orhindin'gon the gear teeth. p y ,i e represents afpockjet or orifice wliich f is forfn'e'd preferably in each "tooth biandn'eiarf the basethereoflforfthe're tiohfofa lubri eating inaterial, such as pow cred pluinbago.-' Said" pockets extend through the ends oi. the

vered I by'fthe end" per-' 'chain' asco inposed of a series arrows of links,

driven wheels, t since 1116 31 d Tin ks. I wheel so firflily asib breveiitdi iaeeinent of the chain, thfgraspingaetidn continuing un- 1 succeeding link i ting-plates b3: The *chain cure the-desired result.

arranged side by si'de, 'The construction of each row of links is substantially the same as that above described, and the several rows of links are arranged to break joints, as clearly shown in Fig. 9. The pivots or pins that connect the links with the plates 12 are in this case of sufficient length to extend across'the eh'ain,"each connecting jseveral links and plates, as shown in Fig. 8. By this constructionof chain, employing a series of rows of links, the independent members of which are arranged to break joints, I enable the chain to be securely engaged with the wheel around which it passes, by the gripping or pinching action which the teeth of the links exert upon the teeth of the wheel at the point where the chain bends in passing around the wheel. By

reference toFigf'Zji't will hejseen'thati 'wheu the'chain is movingin' the direction ind cated said figure', the'first' linkthat,

by the-arrow in p is deflected J from thestrai htj same which theehaiaa'takes b'etweenthe' driving and the to swing outwardly straight portion, as

tronr the plane of the shown at a so; thatftheftooth atthat'end of the'link to oprates air-nine adjacent tooth of thelast link in "the straight "portion of the chain i ii iet esa o h' re es "Tlie'chain is thus caused to grasp the mama link iiitll' straights'eries' reaches "said links. If the'sureach other in passing aroundthewheelsso as to grasp thete'eth oitheflatter. It will be s una, by making thechaih of'aj niiniber screws of links which" hreak joints; th e period aimi g; which theehainjis thus engaged with thewheel is gr'eaterthan when the chain has butone row of' 1inls,because, 'afterone link has grasped andfieleased the "chain," the p n" another rowjgrasps the wheeland continues to hdldthe chain in enjga'ge' entwiththewheel, so that there'is a practicallybontinhousgrasping dfthe wheel by the 'cliain teeth.

in ri srzana sgjfr shq ia 'iiidaifiea'tidh of the guides orjstops used to" prev nt "outward ex ire ofthestraight' p'ortiohs of thechain,

said stops being shown as flanges 0 forined "acumen eirs'ome ef tlie donfititing plates b".

provided The flanges c and wheels 0 are not essential, however, and their office is mainly to prevent strain upon the pivot pins of the upper straight portion of the chain, particularly when said chain is of considerable length. In this case, the wheels a, riding upon' the upper flange 0 cause said flange to'support the weight of the upper straight portion of the chain, as will be readily seen.

The gear wheels used with the chain composed of a plurality of rows of links will have a corresponding pluralityof rows of teeth a, as shown in Figs. 8 and 9. A

The described improvement may be used in any mechanism in which power is transmitted from one wheel to another by flexible connections instead of by direct gearing.

The invention is particularly applicable to bicycles and tricycles, as a substitute for the ordinary sprocket wheels and chains now used. I do not limit myself, however, to this use, and may use the invention for any apparatus to which it may be found capable of application.

The shoulders a are preferably composed of pieces of hardenedsteel or other material, detachably secured to the teeth a by screws a (Fig. 6) or otherwise, so that said shoulders can be replaced by new ones when worn.

The meeting ends of the links I) may be provided with buffer pieces I) b (Fig. 3) of raw hide, or other material which will prevent noise when the links meet the outer edges of the plates b It will be seen that the guides c 0, supporting the straight portions of the chain against outward fiexure, prevent any tensile strain on the chain, the strain being entirely compressive, so that the pivots are not subjected to as great wear as in a chain under tensile strain.

Another advantage resulting from the absence of tensile strain is that the teeth of the chain and of the gear wear alike and remain constantly adjusted to each other, there being no increase of the width of the spaces between the teeth of the chain as there would be if there were a tensile strain tending to pull the links apart and thus wear the pivots.

It will also be seen that the recessed form of the ends of the chain teeth and the insertion of the connecting-plates b into the recesses, enables the inner sides of the links to bear on the outer edges of the plates b so that said plates co-operate with the abutting ends of the links in preventing inward flexure of the chain, the wear caused by the straightening out of the chain being thus'distributed between the ends of the links, the inner sides of the links and the outer edges of the plates 5 The arrangement of the lubricating pockets e is such that said pockets are covered by the plates b in all positions which said links and plates can assume when the chain is running on the gear wheels. Hence there can be no loss of the lubricant nor any escape thereof excepting the desired gradual escape caused by the movement of the plates across the ends of the pockets, while the chain is in use. When it is desired to replenish the lubricant, the chain must be removed and bent abruptly -to swing each pocket away from the plate which normally covers it. The straight portions of the chain being rigid, as already described, act precisely like inflexible racks, in moving on to and 0E from the gear wheels, each of said portions exertinga pushing force on. the wheel toward which it is moving.

The trucks or wheels 0 constitute anti-friction rolls, which run on fixed tracks, and thus prevent strain on the pivots of the links, by the weight of the chain, the outer tracks serving also to prevent outward flexure of the chain. The said anti-friction rolls may be arranged on any suitable part of the chain, so as to project from the side, back or front of the chain.

The advantages resulting from the construction of the chain, due to the reciprocal bearing of the ends of the links against each other, end to end, preventing longitudinal compression of the chain, and to the reciprocal bearing of the inner surfaces of the links against the outer edges of the link-connecting plates or sub-links, preventing inward flexure of the chain, are very marked, and we desire to emphasize the fact that the chain is composed of links pivotally connected and provided with two sets of reciprocal bearingsurfaces, one set represented by the abutting ends of the links I) opposing compressive longitudinal pressure, so that the chain will not be shortened longitudinally by pressure exe'rted upon it, and such pressure will not exert injurious strain and wear upon the pivots represented by the outer edges of the connecting-plates b and the corresponding inner edges of the links 1) bearing upon said outer edges, prevent inward fiexure of the chain.

In another application for Letters Patent of the United States filed by me May 19, 1893, Serial No. 474,743, I have described and claimed a gear chain composed of aplurality of rows of links, each link having gear teeth on the inner side, the links of each row breaking joints with those of the adjacent row and suitable connections between the rows oflinks.

Iclaim- 1. A gear-chain, composed of toothed links, pivotally connected, and provided with two sets of reciprocal bearing surfaces, one set being arranged to oppose compressive longitudinal pressure, while the other opposes inward flexure, as set forth.

2. A gear-chain, composed of a series of toothed links formed and arranged to abut against each other, and a series of sub-links pivotally connected with said abutting links, the said abutting links and sub-links having against inward flexure.

3. A gear-chain, composed of toothed links, and link-connecting plates pivotally coin nected to the links, the links being'arranged set forth.

to abut against each other, end to end, and against the outer edges ofthe plates, whereby inwardfiexure ofthe chain is prevented, as

4. A gear-chain,*which is self-supporting against inward fiexure, and is provided with integral involute gear-teeth at itsi-nnerside; as set forth.

5. A gear-chainywhich is self-supporting against inward flexnre and is provided-with integral gear-teeth, combined with astop or guide arrangedtoprevent outward flexure of a power-transmittingportion of the chain, as set forth. j

6. A gear-chain, composed of links provided'with teeth having-pockets to contain a lubricant, and link-connecting plates pivot ally connected to the links: and arranged to cover the ends of said pockets, as set forth.

7. A gear-chain, composed of links provided with inwardly-projecting gear-teeth,

and link-connecting plates pivotally connected to the links and provided with recesses adapted to receive shoulders on the teeth of a gear-wheel, asset forth.

8. A gear-chain, composed of a plurality of rows of links, each-connectedend to end by pivoted connecting-plates, said links having gear-teeth on their inner sides andbeing arranged so that the links of each row break joints with thelinks of the adjoining row, as

i set forth.

9. A gear-chain,having its links-provided with involute gear teeth and provided with anti-friction rolls,- combined-with a fixed stopguide formed as a'trackto support said antifriction; rolls, as set forth.

In testimony whereof have signed my -na1ne tothis specification, in the presence of two subscribing witnesses; this 3d day of Jane,

JAMES O. BROWN.

- "Witnesses:

. i G. F. BROWN,

A. D. HARRISON. 

